The proposed follow up study of a nonconcurrent cohort of approximately 2000 infertility clinic patients has two primary purposes: a) To evaluate and compare the effectiveness of available medical interventions in producing pregnancies and live births; and b) To assess the magnitude of treatment-independent, or spontaneous, pregnancy rates among these couples. The cohort will be comprised of all couples registering from 1984-87 for infertility evaluation at the Johns Hopkins Hospital. Couples will be identified and followed longitudinally through clinic record abstraction to determine the occurrence and outcome of pregnancy. Record abstraction will yield detailed information on clinical evaluation, treatment experience, and relevant demographic and behavioral variables. Length of follow up will range from 1 to 5 years. Couples who leave the clinic without achieving a pregnancy will be traced for telephone interview in order to learn their pregnancy experience after they left the clinic. A subsample of couples who did achieve a pregnancy while under clinic supervision will also be interviewed by telephone in order to obtain similar information. Comparisons of treatment effectiveness will be made within diagnostic groups. further comparisons will be drawn between: a) Couples who achieve pregnancy during the follow up period and those who do not; b) Pregnancies which are treatment-related and those which are treatment - independent; c) Couples who continue to seek treatments and those who stop before pregnancy occurs; and d) Clinic cohort couples and nationally based profiles of infertility service-seekers. Observed pregnancy and live birth rates will be analyzed using life table methods, logistic regression, and proportional hazards models. Since many factors are associated with the probabilities of successful pregnancy in the absence of intervention, the analysis will adjust for potential confounders, such as diagnosis, duration of infertility, age, primary versus secondary infertility, previous treatment experience, prior contraceptive history, and other demographic and behavioral factors. There is a paucity of comprehensive evaluations of infertility therapy, even though treatment-independent pregnancy is common among some groups of infertile patients. Such an evaluation is critical in light of the high cost, stress, and in some cases, physical pain associated with treatment. Information gained through the proposed study will better inform the treatment-related decisions of couples and clinicians alike.